Coil Issues
Coil Issues I could use some technical help. I just finished the LS swap on my 92 Trans Am running a Terminator X. I took the car for a drive yesterday, maybe 15 minutes, and as I was slowing down to a traffic light my idle was up around 2,000 RPM. I pulled into a parking lot looking for something obvious like a binding throttle linkage or a vacuum leak. Everything looked good so I closed the hood and took the car home so I could diagnose what was up.
In my driveway I shut the car off, let it sit for a minute, and then fired it back up. Again, the idle sat around 2,000 RPM. I checked the IAC position using the handheld and it was up around 50%, but I couldn't understand why it was all of a sudden being commanded to open so much, especially after everything was fine before leaving for my short drive.
I'll spare you all my hours of troubleshooting, but I finally figured out that cylinder #1 wasn't firing. I'm still not sure why, but I was wondering if anyone has ever experienced a coil pack that would only work intermittently? Right now if I start the car up it runs and idles beautifully, and I swapped the coil pack from #1 cylinder to #3 so it'll be easy for me to determine if that was the problem if it happens again, but in all my years of messing with LS engines I've never had a coil pack go bad and only work intermittently. Could it be crapping out when the engine gets hot? Thoughts?
In my driveway I shut the car off, let it sit for a minute, and then fired it back up. Again, the idle sat around 2,000 RPM. I checked the IAC position using the handheld and it was up around 50%, but I couldn't understand why it was all of a sudden being commanded to open so much, especially after everything was fine before leaving for my short drive.
I'll spare you all my hours of troubleshooting, but I finally figured out that cylinder #1 wasn't firing. I'm still not sure why, but I was wondering if anyone has ever experienced a coil pack that would only work intermittently? Right now if I start the car up it runs and idles beautifully, and I swapped the coil pack from #1 cylinder to #3 so it'll be easy for me to determine if that was the problem if it happens again, but in all my years of messing with LS engines I've never had a coil pack go bad and only work intermittently. Could it be crapping out when the engine gets hot? Thoughts?
Appreciate the replies. I did switch the suspect coil to a different location, and I'll have a new replacement here tomorrow just in case. I appreciate the comment about the output test. I got a cable and downloaded the Holley software onto my laptop. This is my first time with the Terminator X and I didn't realize there was so much more functionality when connecting to a computer.
